The present invention relates to a fuse of a semiconductor device, and more specifically, to a fuse of a semiconductor device and a method for forming using the same that may alleviate stress
A semiconductor device such as a memory device and a memory merged logic (MML) includes a plurality of memory cells for storing data. If even one memory cell of a memory array of a semiconductor device has a defect, the whole device is not capable of serving as a memory since the whole device is defective. However, discarding a memory device for the reason that it contains a defective memory cell, a manufacturing yield would be significantly decreased.
In order to improve a manufacturing yield of a memory device, a repair method is required. The repair method in the semiconductor device is performed by replacing a defective memory cell with a redundancy memory cell. In order to replace a defective memory cell with a redundancy memory cell, a fuse is used. In this respect, a semiconductor device is configured to include a plurality of fuses, and these fuses can be cut by a laser. A test is performed to check whether a defective cell exists in a given semiconductor device, and then the fuses are selectively cut depending on a test result.
In the repair method using a redundancy cell, each cell array includes a redundancy word line and a redundancy bit line. When a defect is found in a specific cell, the defective word line or the defective bit line is substituted with the redundancy word line or the redundancy bit line. In the memory device, when a defective cell is found through a test, a circuit is reconfigured to substitute an address corresponding to the defective cell with an address corresponding to the redundancy cell. As a result, when an address signal corresponding to the defective cell is received, the substituted redundancy cell, instead of the defective cell, is accessed.
Of the above-described repair methods, a widely used method is to blow a fuse with a laser beam, thereby performing cell substitution. For this operation, a general memory device includes a fuse unit configured to substitute a defective address path with a new path by blowing the fuse using a laser.